1. Field of the Invention
The present invention relates to a method for preparing a decomposable film of a polymer, and a utilization of this decomposable film. More specifically, it relates to a method for preparing a decomposable film by applying an emulsion containing a specific polymer, and its utilization.
2. Description of the Prior Art
It has been widely carried out that for the purpose of temporarily smoothing a coarse surface or temporarily protecting a surface, the solution of a decomposable polymer is applied and then dried to form a coating film. In this case, the decomposable polymer, when used, is usually dissolved in an organic solvent, but in the case that the employment of the organic solvent is not desirable, an aqueous emulsion has instead been used. For this purpose, an aqueous emulsion which can be obtained by the emulsion polymerization of a methacrylate has been used.
The aqueous emulsion of a polymethacrylate is relatively excellent in thermal decomposition properties, but under oxygen-free or water-free conditions, it is very difficult to completely decompose and vaporize the aqueous emulsion of polymethacrylate, even when heating is carried out. Therefore, this conventional technique has a problem that a large amount of an undecomposed residue remains. In consequence, it is desired to develop an aqueous emulsion of a polymer having excellent decomposition properties.